package com.atguigu.guli.infrastructure.apigateway.filter;

import com.atguigu.guli.common.base.util.JwtUtils;
import com.google.gson.JsonObject;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.core.Ordered;
import org.springframework.core.io.buffer.DataBuffer;
import org.springframework.http.server.reactive.ServerHttpRequest;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

import java.nio.charset.StandardCharsets;
import java.util.List;

/**
 *  自定义filter
 * @author Jc
 */
@Component
public class AuthGlobalFilter implements GlobalFilter, Ordered {
    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {

        ServerHttpRequest request = exchange.getRequest();
        // 判断路径中含有 /api/**/auth/**
        String path = request.getURI().getPath();

        AntPathMatcher antPathMatcher = new AntPathMatcher();
        boolean isAntPathMatch = antPathMatcher.match( "/api/**/auth/**",path);
        // 不放行
        if(isAntPathMatch){

            // 获取token
            List<String> tokenList = request.getHeaders().get("token");
            // 没有token，鉴权失败
            if(tokenList==null){
                ServerHttpResponse response = exchange.getResponse();
                return out(response);
            }

            boolean isCheck = JwtUtils.checkJwtTToken(tokenList.get(0));
            // 校验失败
            if(!isCheck){
                ServerHttpResponse response = exchange.getResponse();
                return out(response);
            }

        }


        // 放行: 使用过滤器链，将请求继续向下传递
        return chain.filter(exchange);
    }



    /**
     * 定义当前过滤器的优先级。值越小，优先级越高
     * @return 0
     */
    @Override
    public int getOrder() {
        return 0;
    }

    /**
     *  使用webflux输入请求信息
     * @param response 响应
     * @return 响应
     */
    private Mono<Void> out(ServerHttpResponse response) {

        JsonObject message = new JsonObject();
        message.addProperty("success", false);
        message.addProperty("code", 28004);
        message.addProperty("data", "");
        message.addProperty("message", "鉴权失败");
        byte[] bytes = message.toString().getBytes(StandardCharsets.UTF_8);
        DataBuffer buffer = response.bufferFactory().wrap(bytes);
        //指定编码，否则在浏览器中会中文乱码
        response.getHeaders().add("Content-Type", "application/json;charset=UTF-8");
        //输出http响应
        return response.writeWith(Mono.just(buffer));
    }
}
